ScsiPortWmiDispatchFunction function (scsiwmi.h)
The ScsiPortWmiDispatchFunction routine is a dispatch routine for miniport drivers that support WMI.
Syntax
BOOLEAN ScsiPortWmiDispatchFunction(
[in] PSCSI_WMILIB_CONTEXT WmiLibInfo,
[in] UCHAR MinorFunction,
[in] PVOID DeviceContext,
[in] PSCSIWMI_REQUEST_CONTEXT RequestContext,
[in] PVOID DataPath,
[in] ULONG BufferSize,
[in] PVOID Buffer
);
Parameters
[in] WmiLibInfo
Pointer to a SCSI_WMILIB_CONTEXT structure that contains registration information for a miniport driver's data blocks and event blocks and defines entry points for the miniport driver's WMI library callback routines.
[in] MinorFunction
Indicates the WMI action to perform. The miniport driver sets MinorFunction to Srb->WmiSubFunction from the input SRB.
[in] DeviceContext
Pointer to a miniport driver-defined context value. The port driver will pass DeviceContext to the miniport driver's HwScsiWmiXxx callback routine. This value would typically point to a HW_DEVICE_EXTENSION structure.
[in] RequestContext
Pointer to a SCSIWMI_REQUEST_CONTEXT structure that contains context information for the WMI SRB. If the SRB can pend, the miniport driver must allocate this structure from the SRB extension because the request context must remain valid until after ScsiPortWmiPostProcess returns with the final SRB return status and buffer size. ScsiPortWmiDispatchFunction will pass RequestContext to the miniport driver's callback routine that processes this request.
[in] DataPath
Pointer to a GUID that represents the data block associated with the request. The miniport driver sets DataPath to Srb->DataPath from the input SRB.
[in] BufferSize
Specifies the size in bytes of the data buffer. The miniport driver sets BufferSize to Srb->DataTransferLength from the input SRB.
[in] Buffer
Pointer to the data buffer. The miniport driver sets Buffer to Srb->DataBuffer from the input SRB.
Return value
ScsiPortWmiDispatchFunction returns TRUE if the request is pending, or FALSE if the request was completed.
Remarks
When a miniport driver receives an SRB in which the Function member is set to SRB_FUNCTION_WMI, it calls ScsiPortWmiDispatchFunction with request parameters, including a pointer to an initialized SCSI_WMILIB_CONTEXT structure. This structure contains information about the miniport driver's data blocks and event blocks and defines entry points for the miniport driver's HwScsiWmiXxx callback routines.
ScsiPortWmiDispatchFunction confirms that the SRB is a WMI request and determines whether the block specified by the request is valid for the miniport driver. If these conditions are met, ScsiPortWmiDispatchFunction processes the SRB by calling the appropriate HwScsiWmiXxx entry point in the miniport driver's SCSI_WMILIB_CONTEXT structure. If the miniport driver does not define an entry point for an optional HwScsiWmiXxx routine, the port driver handles the request.
In either case, after ScsiPortWmiDispatchFunction returns, the miniport driver should do the following for requests that it does not pend:
- Set Srb->DataTransferLength to the value returned by ScsiPortWmiGetReturnSize
- Set Srb->SrbStatus to the value returned by ScsiPortWmiGetReturnStatus
- Call ScsiPortNotification with RequestComplete and again with NextRequest
Requirements
| Requirement | Value |
|---|---|
| Target Platform | Desktop |
| Header | scsiwmi.h (include Miniport.h, Scsi.h) |